Question

Please helppppppppppp

Answer 1

`C=\pi* d`

for the first one

`\begin{gathered} C=\pi*4 \\ C=12.56 \end{gathered}`

for the second one

`\begin{gathered} C=(3.14)*20 \\ C=62.8 \end{gathered}`

and the last one

`\begin{gathered} 28.26=(3.14)* d \\ (28.26)/(3.14)=(3.14* d)/(3.14) \\ d=9 \end{gathered}`